Okay, first things first, understand that reputation do not define your knowledge, it defines that a person that is "Knowledgeable" and or "Adept" has acknowledged your work and wants to show you how they view your work. Now, your work on this site will be judged by those people, and the result of your work will be the reputation you get. Now, if you don't have a seeable reputation doesn't mean you don't have one, there are two reputation types that are invisible to all except "Knowledgeable" and "Adept", they are; "Fluff" and "No Rank". So if you don't have a rank, doesn't mean you are a fluff, it just mean that no one from the "Knowledgeable" or "Adept" ranks have decided on what to rank you as, or you have provide material to the Forums, Chatter, Articles, and or Spells, that will decide anything.

How to get one, you must like stated many times, show your knowledge and maturity. Understand that no one that isn't "Knowledgeable" or "Adept" can rank you, and asking for a rank will be a sure way that you do not get one. Now, plagarism, if you fruad other peoples work and claim it as your own, then get a rank for it, they find out later, they will demote your rank, and possibly get warned by a Moderator.

When a member first joins SoM, they usually write something about themselves. What they write can be a good indication of their beliefs, experience, and/or competence. If they then join in the different discussions on the forums, their reputation will increase. What can the Mods say about a member who writes nothing on his/her profile? Only that they are "Unknown!".
If the member writes things such as "I am a 13 year old vampire" or "I am a mermaid/angel/demon/fairy."
Then the reputation will be zero! But all the Mods, and many knowledgeable members, will help that member to increase their Rank.
However, don't take your "Reputation" too seriously! We are all seeking enlightenment. All searching for truth. We are, all of us, still learning!